. "\"Catalysis of the transfer of a peptide from one side of a membrane to the other, up its concentration gradient. The transporter binds the solute and undergoes a series of conformational changes. Transport works equally well in either direction and is driven by proton movement.\" [GOC:mtg_transport]" . . "proton-dependent peptide secondary active transmembrane transporter activity" . . . . "hydrogen/oligopeptide symporter" .